Feed mechanism for flexible sheets such as envelopes



Jan. 6, 1953 J. R. L AUFFER 2,624,576

FEED MECHANISM FOR FLEXIBLE SHEETS SUCH AS ENVELOPES Filed Feb. 9, 19493 Sheets-Sheet l M j 75 53 4? i E' E JNVENTOR JAM@ AMF/5 J. R. LAUFFERJan. 6, 1953 FEED MECHANISM FOR FLEXIBLE SHEETSv SUCH AS ENVELOPES 3Sheets-Sheet 2 Filed Feb. 9, 1949 SY mw SK .m ML! ghn.

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INVENTOR. 46705 AMF/5@ J. R. LAUFFER Jan. 6, 1953 FEED MECHANISM FORFLEXIBLE SHEETS SUCH AS ENVELOPES 3 Sheets-Sheet 3 Filed Feb. 9, 1949mudhl Re w M ma K e I J m Nw Z .T N. A Ql @@MK ww Patented Jan. 6, 1953FEED MECHANISM FOR FLEXIBLE SHEETS SUCH AS ENVELOPES Jacob R. Lauffer,Valley Stream, N. Y., assignor to Miller-Lauer Printing Equipment Corp.,New York, N. Y., a corporation of New York Application February 9, 1949,Serial No. 75,338

15 Claims.

This invention relates to a mechanism for feeding separate sheets offlexible material such as envelopes. In the embodiment here describedfor purposes of illustration, there is disclosed a mechanism for feedingenvelopes in succession from a stack thereof to a printing position.Most envelopes, and particularly those of crisp paper such as bond, arelikely to be somewhat warped and a stack of such envelopes, moving alonga conveyor, except whenY tightly compressed together exhibit noticeableirregularities of spacing. When compared in the hand, certain envelopesseem to be almost flat; others show deformations ranging from barelyperceptible to very noticeable deviations from complete flatness. Thesedeformations are due to the crispness of the paper, the effects offolding, local shrinkage when the paste dries, humidity and static. Theextent of deformation varies with different kinds of paper, bond paperbeing an extreme example, but is present in almost all envelopes.

The printing of impressions on envelopes has heretofore been donethrough the use of reciprocating feeder devices or presses whose maximumspeed is approximately 10,000 impressions per hour. This speedlimitation is imposed by the nature of the reciprocating mechanismitself, which cannot `be operated at materially higher speeds to producesatisfactory work. While rotary presses can operate on continuous websoi paper at very much higher speeds (up to 100,000 impressions perhour), the diiculties inherent in feeding separated sheets, especiallyfolded and pasted sheets such as envelopes, at these speeds have, so faras l'. am aware, prevented commercial use of rotary presses for printingon separated sheets or on envelopes.`

In my prior application Ser. No. 768,744, led August 15, 1947, now Pat.No. 2,554,577 granted May 29, 1951, I have shown and described a rotaryprinting press for separated sheets such Ias envelopes, in which theenvelopes are engaged under opposite ends of their flaps by a pair ofprojecting lugs carried on two geared-together Ycarrier chains moving inparallel paths, the envelopes being thereby successively extracted oneby one from the leading end of a moving feed stack to and through arotary press and thence to a delivery table. This feeding mechanism i-s'herein sometimes called the onward feeder. 'The present invention wasconceived primarily as an improvement in the feeding mechanism of thepress shown in said prior application, but in ,a more general sensev isbelieved to be useful in connection with the feeding of any kind ofpreviously-separated iiexible sheets, whether or not envelopes, where itis desired to transfer such sheets one at a time from the leading end ofa moving stack thereof towards a point where some further operation,including but not limited to printing, is to be performed upon them.Consequently, while the prior application is referred to as disclosing aprinting press and carrier chains with which the present invention issusceptible of being used, it is expressly pointed out that the presentinvention is not limited to use solely in that connection.

One object of the present invention is to provide a :stationary shapingplate located at or adjacent the translation point-where the sheets areto be withdrawn one by one from a moving stackwhich in cooperation withsuction acting through openings in the plate holds the leading sheet ofthe stack in an exactly predetermined position for the length of timenecessary to enable the onward feeder to gain control of the particularsheet so held.

Ano-ther object is to provide a suction-aided shaping plate which willcompel the leading sheet of the stack to assume momentarily apredetermined shape which will permit it to be taken hold of by anygripping or engaging elements of ithe onward feeder.

Another object is to provide positively-actusated means synchronizedwith the onward feeder to regulate and control the suction so that themaximum eiect thereof will be utilized in drawing the leading sheet ofthe stack into contact with, and compelling it to conform to the shapeof, the shaping plate, and so that the suction effect will then bediminished while the onward feeder is withdrawing the leading sheet fromits position in contact with the shaping plate.

In this specification I show and describe one form of mechanismaccording to my invention for handling relatively large envelopes. Sincethe printing mechanism and other mechanisms for handling and deliveringthe envelopes after ,printing form no part of the present invention, Ido not describe them but merely indicate their general location bylegend on the drawings.

Referring to the drawings which are annexed to and form part of thisspecification- Fig. 1 is a vertical section in a longitudinal planethrough the delivery portions of the mechanism.

Fig. 2 is a top plan View, with some parts cut away, of the mechanismshown in Fig. 1.

Fig. 3 is a front elevation of the shaping member, with its cover plateremoved, substantially in the plane 3 3 of Fig. 4.

Fig. 4 is a vertical section through the shaping member, with its coverplate in place, substantially in the plane 4-4 of Fig. 3.

Fig. 5 is a front elevation on a reduced scale of the shaping member,with its cover plate in place, from the same point of view as Fig. 3.

Figs. 6 to 10 inclusive are partial vertical crosssectional views at thetranslation point, somewhat diagrammatic in character, illustratingsuccessive stages of the envelope action at that point, with the warp ofthe envelopes shown in exaggerated form for purposes of illustration-Fig. 6 shows the leading envelope sucked against and conforming in shapeto the flat face of the shaping member, with its flap drawn against thenap sucker, at the moment the flap has been engaged by the lugs 20 ofthe onward feeder-the bleed valve being fully open;

Fig. 7 shows the leading envelope partially lifted from the stack byupward movement of the lugs, and the lower end of the second envelopebeginning to be sucked toward the lowest openings of the shapingmember-the bleed valve is closing;

Fig. 8 shows the leading envelope lifted almost clear of the shapingmember, and the second envelope being sucked into position against theshaping member by both of the lower openings- 9 the bleed valve is nowfully closed;

Fig. 9 shows the iirst envelope lifted fully clear of the shaping memberand the second envelope almost completely drawn against the shapingmember-the bleed valve is still fully closed; and

shown and others not shown in the drawing,

journal and support the axles on which the various wheels and pinionshereinafter mentioned are rotatably mounted. These vertical supports aremounted upon bed plate II vor secured in fixed relation thereto.

Secured upon shaft I4 are sprocket wheels I5, I5. Secured upon shaft Ioare sprocket wheels Il'. Chains I8, I9 pass over sprocket wheels I5, I5and II, and also over other sprocket wheels (not shown) at least one ofthe sprocket wheels r in the path of each chain being powered byconnection with a suitable motor. The two chains I8 and I9 are arrangedto run in parallel paths a predetermined distance apart. The shaftingand other connections are such that the chains run at the same speed andare maintained in fixed relation to each other as respects forwardmovement. Thus a given link of one chain is always opposite a given linkof the other, at all stages of rotation. At fixed distances apart, alongeach chain, there are provided lugs Eil, 2i projecting laterally of thechain, each mounted upon a suitable bracket 22 secured to one link ofthe chain. Each lug is directed toward a corresponding lug on theopposite chain, the two lugs thus paired pointing towards each other andbeing maintained in alinement during their entire traverse. (See, forexample, lugs 20a and 2m in Fig. 2.)

The two chains, moving in unison and in parallel paths, thus form withtheir paired lugs a carrier for envelopes, designed to transport thelatter one at a time from the translation point, hereinafter described,to a printing position, whose location is indicated generally by alegend on Fig. l, and thereafter to a delivery position beyond theprinting position. In so doing, an opposed pair of lugs engages anenvelope under the opposite ends of the flap thereof, and thus advancesthe envelope to and through a rotary printing mechanism, comprisingprinting and impression rollers. The type cylinder and impressioncylinder are located between the chains, and may imprint on any desiredportion of the envelope without interference from the chains and lugs.What has thus far been described is shown in more detail in my priorapplication Serial No. 768,744, filed August 15, 1947, and referencethereto is made for a more complete understanding of the structureinvolved. The present invention is not concerned with the nature of theprinting or other operations performed upon the envelopes after theyhave come under control of the chains I8, I9, and accordingly thefurther traverse of those chains and operations associated therewith arenot described herein.

If desired, the sprocket wheels serving one chain may be slidablymounted on their supporting shafts, whereby that chain may be movedtoward or away from the other chain, thus adapting the machine to bemanually adjusted for printing envelopes of different Widths.

At one portion of their path of travel the chains I8, I9 move, in theform of mechanism here described, in a substantially vertical plane asshown in Fig. 1. At this portion of their travel the lugs 20, 2I moveupwardly, and during this upward movement they are arranged and adaptedto engage under the opposite ends of the opened flap of an envelope heldfor this purpose in a vertical plane by the mechanism hereinafterdescribed. 'Ihe position occupied by the envelope which is ready to begrasped by lugs 23, 2i is herein termed the "translation poin and isgenerally indicated by the reference character A on Fig. 1.

The feed of envelopes to the translation point A may if desired be inthe form of a compact stack moving in a horizontal Ieed magazine at asuitable speed or speeds under control of powered mechanism tending toadvance the stack toward the translation point, described as follows:

The horizontal feed magazine may contain powered feeding mechanisms suchas the wires 23, 24 mounted over sheaves 25 and driven by a suitablesource of power not shown. Wires 23 and 24, in their upper horizontaltraverse, are arranged to lie upon support plates 2S, 2'I xedlysupported with respect to bed plate II. Similarly supported are sideplates 28 and 29 serving to guide the lateral margins of the stack ofenvelopes supported on wires 23, 24.

If desired, one wire and its supporting sheave and plate, and thecorresponding side plate, may be slidably mounted on their respectivesupporting shafts and mounts, whereby they may be moved toward or awayfrom the other wire and plates, thereby permitting the width of thehorizontal and plates, thereby permitting the width of the horizontalfeed magazine to be manually adjusted for handling envelopes ofdifferent widths.

In slotted supports 49, 49 resting on or in fixed relation to bed plateII is mounted a cross-rod 5I having a series of perforations 52 therein.

Rod 5| passes through slots 50 in the supports and may be adjusted forangular and vertical position by suitable nuts or thumbscrews 53. In aselected perforation of rod 5|, and held there by a thumbscrew, isplaced a hold-back finger 54 having a curved and pointed end adapted torest against the top of the moving stack of envelopes. The position ofthe pointed end may be adjusted and fixed by means of the nuts andthumbscrews mentioned. By suitably adjusting the pressure of the pointedend of finger 54 on the top of the moving stack of envelopes, thisfinger will as pressure builds up behind from the forward movement ofthe stack permit envelopes to escape towards the translation point at aregular rate of speed. In ordinary operation this adjustment is so madethat the envelopes in the stack between the pointed end of finger 54 andthe translation point A (to the left of the finger as seen in Fig. 1)are under substantially less pressure, and are looser, than theenvelopes in the stack approaching the finger (to the right of thefinger as seen in Fig. 1)

For optional use when feeding very tall envelopes, where the stack inthe horizontal feed magazine has a tendency to fall forward or backward,I provide auxiliary chains 30, 3| which, at intervals, carry blocks 32suitably slotted. Into the slots of blocks 32 there may be manuallyinserted a guide plate 33, adapted to be manually removed as the blockreaches the forward end of its upper line of travel. Chains 3| engagewith and are rotated by sprocket wheels 34, 34a and other sprocketwheels not shown, which are suitably powered so that, if the plate 33 isin use, it will advance at substantially the same speed as that at whichthe stack of envelopes is being advanced by wires 23, 24 and willsupport the upper ends of the envelopes.

At the translation point, and generally at right angles to and acrossthe path of travel of the stack feeder, and in or immediately adjacentthe path of travel of the onward feeder, there is positioned a shapingmember or suction box designated generally by the reference character35, and shown in more detail in Figs. 3 to 5 inclusive.

The shaping member comprises a plate, preferably of polished steel orother suitable metal. having a shape such that, when the leadingenvelope is firmly pressed against this plate, said envelope willconform to a predetermined shape when it is at the translation point. Inthe form of machine here described, it is desired that the leadingenvelope shall be flat while at this point` Accordingly, the plate isflat, and is designed to make contact with so much of the surface of theleading envelope presented thereto as is necessary to make saidenvelope, at the moment it is to be lifted by the onward feeder, conformsubstantially to the requirements of flatness which will assure itsaccurate positioning so that each of a pair of lugs 20, 2| of the chainwill accurately come into register with the ends of the flap and willengage and lift the envelope thereby.

In the form of shaping member illustrated in Figs. 3, 4 and 5J theshaping member is boxlike in structure, having an interior chamber. Thisbox-like structure is formed as follows. Secured to base 35 arecontinuous wall members 3l and a cover plate 45. Secured to the base 36is a journal bearing 39 supporting a rotatable shaft 33 whose reducedend |4| extends into the chamber within the shaping member. Secured toreduced end |4| is a valve disc |42 having four slots |43 thereinarranged symmetrically about the shaft, and preferably arc-shaped andequidistant from the center of the shaft. A series of four round vents|44 in base 36 are arranged symmetrically about the center of the shaftwith their centers equidistant therefrom and arranged to register withthe slots |43. The arrangement is such that, as valve disc |42 revolveswith shaft 38, the four vents |44 are simultaneously opened and thenclosed by movement across them of the `slots |43 and intervening lands.Thus, disc |42 serves as a valve for controlling the bleed of air fromatmosphere to the interior of shaping member or suction box 35, such airbeing allowed to bleed and then being prevented from bleeding, inalternation, as disc |42 revolves.

An opening or slot 43, preferably though not necessarily formed of aseries of openings 4|, 4| communicates with tube 44 through whichsuction is drawn by a suitable fan not shown. Suit-V able mounting meansare provided whereby shaping member 35 may be secured on base plate 46in proper position.

Shaft 38 is journalled in cross bar |45 and upon this shaft is secured agear |46 engaging with worm |41 fixed on shaft |48 which is journalledin supports mounted on cross bar |45. Fixed on shaft |48 is a sprocket|49 over which passes a chain |50 that also passes over sprocket |5|secured on shaft |6. The arrangement is such that rotation of shaft I6,in response to movement of the carrier chains |8, I9, causes valve disc|42 within shaping member 35 to rotate at a speed which is proportionalto and in step and synchronism with the movement of the chains.

Cover plate 40 on the shaping member 35 is provided with suitably placedopenings 42.

The number, arrangement and location of these openings in plate 40 is amatter of choice, depending on the character of the sheets (orenvelopes) to be handled. I have in the drawing shown an arrangementcomprising two openings near the bottom of the envelope, two more abouta third the way up from the bottom of the envelope, and` two near theupper corners, which has been succesifully used in handling tallend-opening manilla envelopes. More openings may be used if desired. Theuse of one or more openings near the bottom, and one or more near theupper corners, of the envelope has the special advantages that suctionfrom the lower openings will be operative to draw the lower edge of afollowing envelope towards the plate while a preceding envelope is beingraised but is still in contact with the upper openings. The shapingplate 40 is of such a size as to engage the back of an envelope, beneaththe fiap, leaving the ap free. This permits the flap to ride clear overthe top of the shaping member. Plate 40 therefore engages only the bodyportion of the envelope which is beneath the flap.

Above each end'of the shaping member there is mounted a flap sucker 41,48, each comprising a flared-end tube suitably connected to a source ofsuction, the mouth of the tube being set at an angle to the face of theshaping plate 40 as shown.

As presently advised the invention is believed to comprehend the use ofa shaping plate, whether planiform as is best adapted for handlingenvelopes to be engaged by lugs under their flaps, or curved as may besuited to other types of fiexible sheets which are to be engaged bygripping mechanisms other than lugs, where suction operating through oradjacent the shaping` surface is employed to cause the leading envelopeor sheet to conform to a predetermined shape during the moment it is tobe extracted from the stack.

The operation of the above-described apparatus is as follows:

A stack of envelopes resting on wires 23, 24 (and, if desired. alsoguided and advanced by moving guide plate 33) is moved flap-sidesleading toward translation point A by means of the power applied todrive wires 23 and 24. Holdback finger' 54 releases envelopessuccessively into a zone in front of the translation point where theenvelopes are more loosely arranged in the stack. As the leadingenvelope approaches translation point A, it comes under the influence ofatmospheric air rushing into openings A2 in the face of plate 40 ofshaping member 35, and is thereby caused to be attened against the fiatface of plate 43. This operation does not catch the flap of the leadingenvelope against plate 45 but allows the flap to extend beyond and abovethe surface of shaping member 35. The flap suckers 41, 48 open the flapand hold it in extended position while the envelope is held againstplate 40. The leading envelope, which may left to itself be considerablywarped or misshapen, is thus compelled to assume a flat position, withits flap outwardly extended, at the moment when the opposite ends of itsflap are to be engaged by the lugs 2Q, 2| of the onward deliverymechanism.

The timing of valve disc |62 in relation to the arrival and departure ofenvelopes at the translation point is so arranged (through the chain |53and worm |47, Figs. l and 2) that the bleed vents |44 are closed duringthe time the leading envelope in the stack is to be drawn toward thesurface of the shaping plate in a direction normal to that surface, andare open during the time that an envelope in contact with said surfaceis to be moved away in a direction parallel thereto. Consequently, thesuction operatesrwith maximum force to move an envelope towards theplate (to the left as seen in Fig. 1 and Figs. 6 to 10), and is reducedto a minimum, by reason of the bleed, when the chain and lugs are movingthis envelope from in contact with the plate (upwardly as seen 'in Fig.1 and Figs. 6 to 10). By this arrangement the suction applied throughopenings 42 iiuctuates in a regular and cyclic manner between maximumand minimum in timed relation to the approach and departure ofsuccessive envelopes at the translation point.

This operation is illustrated in 6 to 10, inclusive.

In Fig. 6, which shows lugs 2t in engagement with the flap of theleading envelope and about to move this envelope upwardly, the bleedvent |44 is open because slot |43 of valve lili! is in registrytherewith. At this stage, because atmospheric air is bleeding into theinterior of shaping member or suction box 35, the suction effect throughopenings 42 is at a minimum.

In Fig. 7, the leading envelope has been raised to some extent and bleedvent IM is beginning to close.

In Fig. 8, the bleed vent has entirely closed and the second envelope isbeing drawn against plate 40 by the full force of the suction which isnow exerting itself unmitigated by bleed. While the bleed valve may bethus closed before the rst envelope has fully cleared the upper openings42, in order to allow vacuum to build up rapidly in the interior ofshaping member 35 and thus hasten the movement of the second envelope,this will not interfere with the further movement of the first envelopewhen it has reached the point shown.

In Fig. 9 the bleed hole is still closed, and the second envelope isbeing drawn firmly against plate 42 by the full force of the suction.

In Fig. 10, the bleed hole has begun to be opened by arrival of theleading edge of a succeeding slot |43 opposite hole |44. Consequentlythe vacuum in the interior of the member 35 is beginning to bediminished by inrush of atmospheric air, and the force tending to pressthe second envelope against the plate 40 is beginning to diminish. Atthis stage flap sucker 41 is drawing the nap of the second envelope tofull open position where it will be in readiness to be engaged by thenext pair of lugs 2|), 2|.

The result is that positively-actuated means are provided, synchronizedwith the movement of the lugs of the onward feeder, to assure that thesuction is at maximum value when an envelope is being drawn towards theplate in a direction normal to its surface, and at minimum value when anenvelope is lifted away from the plate in a direction parallel to itssurface.

While I have herein shown and described, with certain alternates andmodifications, the best form of apparatus known to me whereby theadvantages of the invention may be realized, I do not intend that theinvention shall be limited to the particular form in which the inventionis illustrated, but that it shall be taken as embracing all forms andsubcombinations thereof comprehended within the following claims.

I claim as my invention:

l. In a machine for feeding flexible sheets, the combination of a stackfeeder, an onward feeder for advancing one by one sheets taken from thestack, the paths of travel of said feeders intersecting at substantiallyright angles, a plate positioned immediately adjacent the path of travelof the onward feeder and across the path of travel cf the stack feeder,suction openings located in the plate surface to draw the leading sheetin the stack toward the plate and to conform said sheet to apredetermined shape at the moment it is to be engaged by the onwardfeeder, vents open to atmosphere in communication with said suctionopenings, and a bleed valve alternately opening and closing said vents,said valve ybeing driven in synchronism with the onward feeder andarranged to open said vents and thus to reduce said suction when saidsheet is to be engaged by the onward feeder.

2. In a machine for feeding flexible sheets, the combination of astationary shaping plate, power-driven feeding mechanism forcontinuously advancing a stack of said sheets with their facesjuxtaposed in such manner that the leading sheet approaches said platefrom a direction generally normal to the surface thereof, a suctionopening in said plate adapted to draw the leading sheet into engagementwith the plate and thus cause it to conform in shape to the shape of theplate, power-driven feeding mechanism adapted to remove successiveleading sheets one by one from a position of engagement with the surfaceof the shaping plate in a direction generally parallel to said surface,and a bleed valve driven in synchronism with the last-named feedingmechanism and adapted to open and thus to reduce said suction when asheet is to be removed from engagement with said plate.

3. In a machine for feeding envelopes, the

combination of a horizontal envelope stack feeder, an envelope feederfor extracting envelopes vertically from the stack one at a time byengagement with their naps, a vertical plate positioned across the pathof travel of the stack feeder and substantially in the plane in whichenvelopes are to be extracted therefrom, suction openings adjacent theplate surface adapted to draw the body of the leading envelope towardthe plate and thereby conform it to a predetermined shape with its fiapclear of the surface of the plate, and a bleed valve driven insynchronism with said second-mentioned feeder and arranged to open andthus reduce the suction when an envelope is to be extracted from thestack.

4. In a machine for feeding envelopes, the combination of a horizontalenvelope stack feeder, an envelope feeder for extracting envelopesvertically from the stack one at a time by engagement with their flaps,a vertical plate positioned across the path of travel of the stackfeeder and substantially in the plane in which envelopes are to beextracted therefrom, suction openings adjacent theV plate surfaceadapted to draw the body of the leading envelope toward the plate andthereby conform it to a predetermined shape with its ap clear of thesurface of the plate, a flap sucker adjacent said plate surface adaptedto open the flap of an envelope held against the plate, and a bleedvalve driven in synchronism with said second-mentioned feeder andarranged to open and thus reduce the suction when an envelope is to beextracted from the stack.

5. In a machine for feeding flexible sheets, the combination of meansfor causing a stack of said sheets to be delivered so that a portion ofthe surface of the leading sheet is presented against the surface of ashaping plate, at least one suction opening adjacent the plate surfaceadapted to be covered by the leading sheet when the latter comes to restagainst the plate, a passageway communicating with said opening forsucking air through said opening to draw said sheet toward the plate,bleed vent open to atmosphere communicating with said passageway, and apower-operated valve arranged alternately to open and close said bleedvent from said passageway to the atmosphere thereby alternatelydecreasing and increasing the suction effect through said opening.

6. In a machine for feeding exible sheets, the combination ofpower-driven feeding mechanism for continuously advancing a stack ofsaid sheets with their faces juxtaposed and delivering the leading sheetagainst the surface of a shaping plate, a suction opening adjacent theplate surface adapted to be covered by the leading sheet when the lattercomes to rest against the plate, a passageway communicating with saidopening for sucking air through said opening to draw said sheet towardthe plate, a bleed vent open to atmosphere communicating with saidpassageway, and a power-operated valve arranged alternately to open andclose said bleed vent from said passageway to the atmosphere therebyalternately decreasing and increasing the suction effect through saidopening.

'7. In a machine for feeding flexible sheets, the combination of astationary shaping plate, means for causing a stack of said sheets to bemoved toward the surface of said plate in such manner that the leadingsheet approaches said plate from a direction generally normal to thesurface thereof, an opening in said plate adapted to be covered by theleading sheet when said sheet comes in contact with the plate, apassageway communicating with said opening for sucking air through theopening, power-driven feeding mechanism adapted to move successiveleading sheets one by one from in contact with the surface of theshaping plate in a direction generally parallel to said surface, and ableed valve driven in synchronism with the last-named feeding mechanismand adapted to open and thus to reduce said suction when a sheet is tobe removed from engagement with said plate.

8. In a machine for feeding envelopes, the combination of means forcausing a stack of said envelopes to be delivered so that a portion ofone lateral surface of the leading envelope is presented against ashaping plate, at least one suction opening adjacent the plate surfaceadapted to be covered by the envelope when the latter comes in contactwith the plate,.a passageway communicating with Ysaid opening forsucking air through the opening and thus drawing the envelope towardsthe plate, power-driven feed mechanism adapted to engage under theopposite ends of the flap of the leading envelope while it is in contactwith the plate and to move said envelope away from the plate in adirection generally parallel to the surface thereof, and a bleed valvedriven in synchronism with said last-named feed mechanism arranged toopen and thus reduce the suction when an envelope is to be moved awayfrom the plate. y

9. In a machine for feeding envelopes, the combination of means forcausing a stack of said envelopes to be delivered so that a portion ofthe flap side of the leading envelope is presented against a shapingplate with the flap free of the plate, at least one suction openingadjacent the plate surface adapted to be covered by the envelope whenthe latter comes to rest against the plate, a passageway communicatingwith said opening for sucking air through the opening and thus drawingthe envelope towards the plate, and a power-operated valve arrangedalternately to open and close a bleed vent from said passageway to theatmosphere thereby alternately decreasing and increasing the suctioneffect through said opening.

10. In a machine for feeding envelopes, the combination of means forcausing a stack of said envelopes to be delivered so that a portion ofthe flap side of the leading envelope is presented against a shapingplate with the flap free of the plate, at least one suction openingadjacent the plate surface adapted to be covered by the envelope whenthe latter comes in contact with the plate, a passageway communicatingwith said opening for sucking air through the opening and thus drawingthe envelope towards the plate, power-driven feed mechanism adapted toengage under the opposite ends of the ap of the leading envelope whileit is in contact with the plate and to move said envelope away from theplate in a direction generally parallel to the surface thereof, and ableed valve driven in synchronism with said last-named feed mechanismarranged to open and thus reduce the suction when an envelope is to bemoved away from the plate ll. In a machine for feeding envelopes, thecombination of means for causing a stack of said envelopes to bedelivered so that a portion of the flap side of the leading envelope ispresented against a shaping plate with the flap free of the plate, atleast one suction opening 11 substantially in the plane of the plateadapted to be covered by the envelope when the latter comes in contactwith the plate, a passageway coinmunicating with said opening forsucking air through the opening and thus drawing the -envelope towardsthe plate, power-driven feed mechanism adapted to engage under theopposite ends of the flap of the leading envelope while it is in contactwith the plate and to move said envelope away from the plate in adirection generally parallel to the surface thereof, suction means toraise the fiap of the leading envelope into elevated position while theenvelope is in contact with the plate, and a bleed valve driven insynchronism with said feed mechanism and arranged to open and thus toreduce said suction when the flap has been raised.

12. In a machine for feeding envelopes to a printer, the combination ofa stationary shaping plate, power-driven feeding mechanism forcontinuously advancing a stack of envelopes flapsides leading towardsthe surface of said plate so that the leading envelope approaches saidplate from a direction generally normal to said surface, said platebeing so shaped that the flap of the leading envelope remains free ofthe plate when the body of the envelope comes in contact with the plate,a plurality of suction openings in the plate adapted to draw the body ofthe envelope toward the plate and to conform it in shape to the shape ofthe plate, power-driven feeding mechanism engaging under opposite endsof the flap of the thus-conformed leading envelope to withdraw it from aposition in contact with the plate and to advance it towards printingposition, suction means to raise the ap of said envelope into elevatedposition while the envelope is in contact with the plate, and a bleedvalve driven in synchronsm with said feed mechanism and arranged to openand thus to reduce said suction when the flap has been raised.

13. In an envelope handling machine, a suction box for momentarilyholding an envelope in a predetermined position in which it may beengaged by an onward feeder, said box having a vent open to atmosphere,and a powered valve for alternately opening and closing said vent toatmosphere and driven by the feeder to open the vent for bleeding air tothe suction box when the envelope is to be engaged by the feeder toreduce suction on the envelope at that time.

14. In an envelope handling machine, a powerdriven feeder adapted toextract envelopes one by one from a moving stack thereof, a suction boxpositioned across the path of travel of envelopes in the stack andarranged to draw envelopes one at a time from the stack and to hold themin position to be engaged by the feeder, said box having a vent open toatmosphere, and a powered valve for alternately opening and closing saidvent to atmosphere and driven in synchronism with the feeder tov openthe vent for bleeding air to the suction box when an envelope held bythe box is to be extracted by the feeder to reduce suction on theenvelope at that time.

15. In an envelope handling machine, a powerdriven feeder adapted toextract envelopes one by one from a moving stack thereof, a suction boxpositioned across the path of travel of envelopes in the stack andarranged to draw envelopes one at a time from the stack and to hold themin position to be engaged by the feeder, said box having a vent open toatmosphere, and a powered bleed valve for the box for alternatelyopening and closing said vent to atmosphere and driven in synchronismwith the feeder and adapted to close the vent when an envelope is to bedrawn towards the box to apply full suction to the envelope at that timeand to open the vent when an envelope is to be extracted by the feederto then reduce suction on the envelope.

JACOB R. LAUFFER.

REFERENCES CITED The following references are of record in the le ofthis patent:

UNITED STATES PATENTS Number Name Date Re.2l0,862 Harrold Sept. 20, 1933'769,927 Zeh Sept. 13, 1904 955,112 Abrams Apr. 12, 1910 1,724,199 HoagAug. 13, 1929 2,449,690 Chapman Sept. 21, 1948

